Oil the Lower Carboiiiferuus Coal-measures of British America. 73 



at Caribou Cove and elsewhere ; the marine limestones and gypsums, 

 and the underlying sandstones and shales, are seen at Plaister 

 Cove ; also at Right's River, and St. Mary's River. 



In Nova Scotia these older coal-measures, as compared with the 

 true coal-measures, are more calcareous, more rich in remains of 

 fishes, and have fewer vegetable remains, and indications of terres- 

 trial surfaces. They occur generally along the margins of the coal- 

 areas, near their old shores ; and, as might be expected under such 

 circumstances, they are associated with or replaced by beds of con- 

 glomerate derived from the neighbouring highlands of Devonian or 

 Silurian rocks. When the conglomerates are absent, alternations of 

 sandstones with sandy and calcareous shales occur, with frequent 

 changes in character of the organic remains, the general aspect 

 being that of muddy estuarine deposits, accumulated very slowly, 

 and discoloured by decaying organic substances. The supply of 

 sediment, and the growth and preservation of vegetable matter, 

 appear to have been generally on a smaller scale in this early carbo- 

 niferous period than subsequently. In those districts where the true 

 coal-measures are least developed the lower series is most important; 

 showing that the physical and vital conditions of the Coal-measures 

 originated as early as those of Mountain-limestone ; and that locally 

 these conditions may have been contemporaneous throughout the 

 whole period ; but that in some localities the estuary and swamp 

 deposits first formed were complete^ submerged and covered by 

 oceanic deposits, whilst in others early marine beds were elevated 

 and subjected to the conditions of gradual subsidence and vegetable 

 growths indicated in the great coal-measures of the South Joggins, 

 Pictou, and Sidney. 



la Nova Scotia the Lower Coal-measures are characterized by a 

 great preponderance of Lepidodendra (especially L. elegans) and 

 Poacites. The Middle Coal-measures are rich in Sigillarice and 

 Ferns, as well as Lepidodendra. The Upper Coal-measures especially 

 abound in Conifers, Calamites, and Ferns. Palaoniscus, Gyrolepis 

 or Acrolepis, Centrodus, Rhizodus, and Ctenacanthus are the chief fossil 

 fishes of this Lower Carboniferous series. Unio-like shells are 

 nearly the only remains of Molluscs. 



2. " On the Structure of Stigmaria ficoides." By E. W. Binney, 

 Esq., F.G.S. 



The author, having lately met with several specimens of this singular 

 root which exhibit good structural characters, was enabled in this 

 paper to throw some additional light on the origin of the medullary 

 rays in Stigmaria, the nature of the vascular bundles which were 

 believed to be dispersed throughout its pith, and the structure of the 

 central or vascular portion of its rootlet, — points of considerable 

 interest, and which up to the present time have not been well de- 

 termined. Mr. Binney confirms Dr. Hooker's view of the medullary 

 rays having originated in the cellular axis of the stem. The axis, in 

 one of the author's specimens, is seen to be filled with eleven or 

 twelve large vessels, each about ^,th of an inch in diameter, and 

 having very thick walls : these elongated utricles lie close together. 



